Some time ago I became interested in fartleks. When I went out to run in this way, I had to memorize the complete session and look continuously to my watch to see if I had to change the pace. So I decided to make an app to alert me when to change my pace and tell me the pace itself. Moreover it would allow me to stop worrying about having memorized the entire plan.

With MyFartlek you can create your fartlek session adding all steps (rhythm changes) you're going to do and indicating the length of each one. Then you can choose to run any saved fartlek and your phone will speech you when to change pace and how fast to run.